CVE-2024-42979 identifies a stack-based buffer overflow vulnerability in the Tenda FH1206 router firmware version v02.03.01.35. The vulnerability resides in the frmL7ProtForm function, which processes the 'page' parameter from HTTP POST requests. Improper handling of this parameter allows an attacker to overflow the stack, leading to a Denial of Service (DoS) by crashing or destabilizing the device. This vulnerability is classified under CWE-121 (Stack-based Buffer Overflow). The attack vector is remote and requires no authentication or user interaction, making it accessible to any attacker with network access to the device's management interface. The CVSS v3.1 base score is 6.5, indicating a medium severity level primarily due to the impact on availability without compromising confidentiality or integrity. No patches or mitigations have been officially released at the time of publication, and no exploits have been observed in the wild. The vulnerability could be exploited by sending a specially crafted POST request to the vulnerable endpoint, causing the router to crash or reboot, resulting in service disruption.

The primary impact of CVE-2024-42979 is a Denial of Service condition on affected Tenda FH1206 routers. This can disrupt network connectivity for users relying on these devices, potentially affecting home users, small businesses, or branch offices that use this router model. While the vulnerability does not allow data theft or modification, the loss of availability can interrupt business operations, degrade user experience, and increase operational costs due to downtime and troubleshooting. In environments where these routers serve as critical network gateways or are part of larger network infrastructures, the DoS could cascade to affect broader network availability. Since the attack requires no authentication and can be performed remotely, it poses a risk of exploitation by opportunistic attackers or automated scanning tools. The absence of known exploits in the wild currently limits immediate risk, but the medium severity score and ease of exploitation warrant proactive mitigation.

To mitigate CVE-2024-42979, organizations should first verify if they are using the Tenda FH1206 router with firmware version v02.03.01.35. Until an official patch is released, network administrators should restrict access to the router's management interface by implementing network segmentation and firewall rules that limit HTTP POST requests to trusted sources only. Disabling remote management features or changing default management ports can reduce exposure. Monitoring network traffic for unusual POST requests targeting the frmL7ProtForm endpoint can help detect attempted exploitation. Additionally, organizations should maintain an inventory of affected devices and subscribe to vendor advisories for timely patch releases. If possible, consider replacing vulnerable devices with models that have active security support. Employing intrusion detection/prevention systems (IDS/IPS) with custom signatures to detect malformed POST requests targeting this vulnerability can provide an additional layer of defense.